A person does not know what he/she is talking about when he/she says that moss does not affect the roof. In fact moss is a live thing and to need to grow it needs to eat like all living organisms do.
Removing the moss is a very simple process that you can do yourself with a few simple tools and a good moss cleaning product.
To remove the moss from your roof do not use bleach or chlorine based products, as it will though kill the moss but with that it will also prove harmful for your home. These harmful products are not structured to stick to arena roofs; they wipe equally and generally leave behind marks on the roof shingles or tile.
Besides leaving a mark on the roof, these chlorine items posses harsh chemicals that strongly dry out your roofing material giving cracks and making your roofing more prone to the wind disaster. These dangerous items may also kill any plant, shrub or sections of lawn that spreads the roof.
To clean moss from the roof, there are many products especially designed, but a good product will be designed to sick to even the steepest arena roof while hitting the roots of the moss. Also the product which is to be used for washing the roof must be eco-friendly, such that it wont cause any damage to your yard. The product to be used should not leave any mark in the roof.
It is necessary to wipe out the moss from the root, hence always choose a good moss cleaning product which will directly hit the roots of the moss. It would be better if a garden style pump sprayer is used to remove the moss and to clean the roof.
With the help of a medium class bristle scrub brush the moss from the roof can be removed. It is the best way to remove the moss. Brush the moss only when it is wet along with the moss cleaning product, so that the roots of the moss will come off easily.
Only the flower of the roof moss will be removed if you brush the roof moss dry or you use the wrong product, the moss will bloom once again. Once the moss is rubbed from the roof, thoroughly rinse it with water. You may also choose that once the roof is washed thoroughly, spread one more coat of roof cleaner and allow it as it is on the roof.